Pass exit status to parent on Ctrl+D

Reproducer:

    $ ksh
    $ false
    $ ^D
    (child ksh exits)
    $ echo $?
    0

Expected output: 1, the exit status of 'false'. All shells except
ksh93 pass the exit status of the last-executed command and this is
also the POSIX standard behaviour.

src/cmd/ksh93/sh/main.c: exfile():
- At the 'eof_or_error:' label, add a missing restore of the
  current exit status before jumping to 'done'.

NEWS

@@ -14,6 +14,9 @@ Uppercase BUG_* IDs are shell bug IDs as used by the Modernish shell library.
 - Fixed a bug, introduced on 2023-06-02, that made it impossible within a
   namespace to unset a function defined outside the namespace.
 
+- Fixed: ksh didn't pass the exit status of the last command it executed to
+  the parent process on entering EOF (Ctrl+D) on a terminal.
+
 2024-02-09:
 
 - Fixed multiple inaccurate or missing values in the /opt/ast/bin/getconf

src/cmd/ksh93/sh/main.c

@@ -569,6 +569,7 @@ static void	exfile(Sfio_t *iop,int fno)
 				sfclrerr(iop);
 				continue;
 			}
+			sh.exitval = sh.savexit;
 			goto done;
 		}
 		sh.exitval = sh.savexit;